AI Article Synopsis
- NF-κB plays a crucial role in immune response and cell survival, and its deregulation is linked to chronic inflammation and cancer, impacting genes like IκBα and A20 that help regulate it.
- DSIF, when functional, helps process mRNA for these genes, but its knockdown leads to reduced protein levels of IκBα and A20 while extending NF-κB activation.
- The study finds that a significant portion of IκBα and A20 mRNA is improperly processed and retained in the nucleus, highlighting the importance of DSIF in mRNA processing during hypophosphorylated elongation.
Article Abstract
NF-κB is central for immune response and cell survival, and its deregulation is linked to chronic inflammation and cancer through poorly defined mechanisms. IκBα and A20 are NF-κB target genes and negative feedback regulators. Upon their activation by NF-κB, DSIF is recruited, P-TEFb is released, and their elongating polymerase II (Pol II) C-terminal domain (CTD) remains hypophosphorylated. We show that upon DSIF knockdown, mRNA levels of a subset of NF-κB targets are not diminished; yet much less IκBα and A20 protein are synthesized, and NF-κB activation is abnormally prolonged. Further analysis of IκBα and A20 mRNA revealed that a significant portion is uncapped, unspliced, and retained in the nucleus. Interestingly, the Spt5 C-terminal repeat (CTR) domain involved in elongation stimulation through P-TEFb is dispensable for IκBα and A20 regulation. These findings assign a function for DSIF in cotranscriptional mRNA processing when elongating Pol II is hypophosphorylated and define DSIF as part of the negative feedback regulation of NF-κB.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.celrep.2012.08.041 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!